/Engine/Source/Editor/UnrealEd/Classes/Editor/EditorEngine.h
Creates an GameInstance with the given settings. A window is created if this isn't a server.
virtual [UGameInstance](API\Runtime\Engine\Engine\UGameInstance) * CreateInnerProcessPIEGameInstance ( [FRequestPlaySessionParams](API\Editor\UnrealEd\FRequestPlaySessionParams) & InParams, const [FGameInstancePIEParameters](API\Runtime\Engine\Engine\FGameInstancePIEParameters) & InPIEParameters, int32 InPIEInstanceIndex )